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Speleology in Kazakhstan

Shakalov on 04 Jul, 2018
Hello everyone!   I pleased to invite you to the official site of Central Asian Karstic-Speleological commission ("Kaspeko")   There, we regularly publish reports about our expeditions, articles and reports on speleotopics, lecture course for instructors, photos etc. ...

New publications on hypogene speleogenesis

Klimchouk on 26 Mar, 2012
Dear Colleagues, This is to draw your attention to several recent publications added to KarstBase, relevant to hypogenic karst/speleogenesis: Corrosion of limestone tablets in sulfidic ground-water: measurements and speleogenetic implications Galdenzi,

The deepest terrestrial animal

Klimchouk on 23 Feb, 2012
A recent publication of Spanish researchers describes the biology of Krubera Cave, including the deepest terrestrial animal ever found: Jordana, Rafael; Baquero, Enrique; Reboleira, Sofía and Sendra, Alberto. ...

Caves - landscapes without light

akop on 05 Feb, 2012
Exhibition dedicated to caves is taking place in the Vienna Natural History Museum   The exhibition at the Natural History Museum presents the surprising variety of caves and cave formations such as stalactites and various crystals. ...

Did you know?

That permafrost is ground that is perennially below the freezing point of water [16].?

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Featured articles from Cave & Karst Science Journals
Chemistry and Karst, White, William B.
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Featured articles from other Geoscience Journals
Karst environment, Culver D.C.
Mushroom Speleothems: Stromatolites That Formed in the Absence of Phototrophs, Bontognali, Tomaso R.R.; D’Angeli Ilenia M.; Tisato, Nicola; Vasconcelos, Crisogono; Bernasconi, Stefano M.; Gonzales, Esteban R. G.; De Waele, Jo
Calculating flux to predict future cave radon concentrations, Rowberry, Matt; Marti, Xavi; Frontera, Carlos; Van De Wiel, Marco; Briestensky, Milos
Microbial mediation of complex subterranean mineral structures, Tirato, Nicola; Torriano, Stefano F.F;, Monteux, Sylvain; Sauro, Francesco; De Waele, Jo; Lavagna, Maria Luisa; D’Angeli, Ilenia Maria; Chailloux, Daniel; Renda, Michel; Eglinton, Timothy I.; Bontognali, Tomaso Renzo Rezio
Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria), Briestensky, Milos; Rowberry, Matt; Stemberk, Josef; Stefanov, Petar; Vozar, Jozef; Sebela, Stanka; Petro, Lubomir; Bella, Pavel; Gaal, Ludovit; Ormukov, Cholponbek;
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Your search for spectral-analyses (Keyword) returned 7 results for the whole karstbase:
THE DISCHARGE VARIABILITY OF SOME KARST SPRINGS IN BULGARIA STUDIED BY TIME-SERIES ANALYSIS, 1995, Pulidobosch A. , Padilla A. , Dimitrov D. , Machkova M. ,
The discharge variability of some karst springs in Bulgaria has been investigated in detail within a region situated in the semiarid zone where most of the principal processes controlling spring outflow (evapotranspiration, snow accumulation, karstic functioning) are significant. While the karstification was notable in the Kotel and Bistretz springs with a predominance of quickflow, in the Beden system the baseflow was higher and had a behaviour similar to a porous aquifer. Univariate and bivariate spectral analyses were applied as a suitable tool in preparation for a further application of precipitation-discharge relationship models

Contribution of correlation and spectral analyses to the regional study of a large karst aquifer (Charente, France), 1998, Larocque M. , Mangin A. , Razack M. , Banton O. ,
The purpose of the study is to demonstrate that correlation and spectral analyses can contribute to the regional study of a large karst aquifer. An example is presented for the La Rochefoucauld karst aquifer (Charente, France). Different types of spatially distributed time series provide valuable spatio-temporal information for the karat aquifer. The available time series consist of the spring flow rates, the flow rates at different locations in sinking streams, the piezometric levels, the electrical conductivity and temperature of the water, the atmospheric pressure and the precipitation The analysis of the flow rates at the springs shows that the aquifer empties very slowly and has a large storage capacity. Hydrodynamic links were established between three of the four rivers flowing on the aquifer and the springs. The results also demonstrate the important spatial heterogeneity of the aquifer and indicate that the most rapid flow occurs in the northern part of the aquifer. Hourly piezometric and electrical conductivity time series indicate that the transmissivity of the aquifer varies when some conductive channels become desaturated during the low water period. The delays between the distributed recharge and the piezometric level, between the localized river input and the how rates at the springs and between the electrical conductivities in rivers and the main spring provide information on the travel times in the aquifer, The observation of earth tides and barometric effects indicate that this apparently unconfined aquifer has a confined behaviour. (C) 1998 Elsevier Science B.V. All rights reserved

Transient-state history matching of a karst aquifer ground water flow model, 2000, Larocque M. , Banton O. , Razack M. ,
Ground water flow modeling in a karst aquifer presents many difficulties. In particular, the hydrodynamic properties and the now behavior can vary over time. History matching of transient-state conditions is required to test the accuracy of the model under varying hydrodynamic conditions. The objective of this study was to illustrate how transient-state conditions can be used to history match a ground water flow model of a large aquifer, the La Rochefoucauld karst (Charente, France). The model used a porous medium equivalent and was based on a steady-state calibration of hydraulic conductivities. The history match consisted of studying the simulated heads and spring flow rates to test the capacity of the model to reproduce different aspects of the aquifer behavior, The simulated heads and flow rates were analyzed as new data using correlation and spectral analyses to compare the temporal structures of the measured and simulated time series. The analyses provided information on the storage capacity of the aquifer, the input-output delays, the degree of correlation between input and output, and the length of the impulse response of the aquifer, These data were used to study the impact of the hypotheses underlying the model (hydraulic conductivities, storage coefficient, representation of rivers, use of a porous medium equivalent). The results show that the model adequately simulates the overall behavior of the studied aquifer, The model can be used under variable hydrodynamic conditions to simulate ground water flow on a regional scale. This case study illustrates how a complete history match of a simplified representation of reality can lead to an adequate mathematical tool

Rainfall-runoff relations for karstic springs. Part I: convolution and spectral analyses, 2000, Labat D. , Ababou R. , Mangin A. ,
Karstic basins contain large reserves of subsurface water. In this paper, three karstic systems located in the Pyrenees Mountains (Ariege, France) are studied. Long records of rainfall and discharge rates for these karstic springs are available, sampled at different rates: daily, hourly and half-hourly. This study aims at illustrating and assessing the capabilities and limitations of linear black-box methods for analysing rainfall-runoff type relationships and reconstructing runoffs from rainfall rate data using such systems. In this study, precipitation and discharge rates are considered as two autocorrelated and cross-correlated stochastic processes. A Linear and stationary rainfall-runoff model is adopted, which is used for identification and simulation purposes. Different versions are analysed, including a model based on a convolution integral between the precipitation rate P(tau) and a transfer function h(t - tau) which can be thought of as the unit impulse response of the system. It is shown that this linear stochastic model (i.e. the statistical version), although accurate in some respects, does not represent the hydraulic behaviour of the system very well during low flow episodes and floods. It is also shown that the use of Fourier analysis, alone, does not lead to a satisfactory reconstitution of observed runoff sequences. For these reasons, the use of non-linear random process input-output models based on Volterra integral series is proposed and discussed. (C) 2000 Elsevier Science B.V. All rights reserved

Introduction of wavelet analyses to rainfall/runoffs relationship for a karstic basin: The case of Licq-Atherey karstic system (France), 2001, Labat D. , Ababou R. , Mangin A. ,
Karstic systems are highly heterogeneous geological formations characterized by a multiscale temporal and spatial hydrologic behavior with more or less localized temporal and spatial structures. Classical correlation and spectral analyses cannot take into account these properties. Therefore, it is proposed to introduce a new kind of transformation: the wavelet transform. Here we focus particularly on the use of wavelets to study temporal behavior of local precipitation and watershed runoffs from a part of the karstic system. In the first part of the paper, a brief mathematical overview of the continuous Morlet wavelet transform and of the multiresolution analysis is presented. An analogy with spectral analyses allows the introduction of concepts such as wavelet spectrum and cross-spectrum. In the second part, classical methods (spectral and correlation analyses) and wavelet transforms are applied and compared for daily rainfall rates and runoffs measured on a French karstic watershed (Pyrenees) over a period of 30 years. Different characteristic time scales of the rainfall and runoff processes are determined, These time scales are typically on the order of a few days for floods, but they also include significant half-year and one-year components and multi-annual components. The multiresolution cross-analysis also provides a new interpretation of the impulse response of the system. To conclude, wavelet transforms provide a valuable amount of information, which may be now taken into account in both temporal and spatially distributed karst modeling of precipitation and runoff

REE3 and Mn2 activated cathodoluminescence in lateglacial and Holocene stalagmites of central Europe: evidence for climatic processes?, 2004, Richter Detlev K. , Gotte Thomas, Niggemann Stefan, Wurth Georg,
Combined visual cathodoluminescence (CL) and spectral analyses of CL reveals periodic enrichments of rare earth elements (REE3) and manganese (Mn2) within the laminations of eight calcitic lateglacial to postglacial stalagmites. In the annual layers, the enrichment of trace elements can be correlated with the autumn/winter laminae, which are strongly pigmented and rich in organic carbon. During the Holocene, they occur especially in the Atlantic stage and in subrecent/recent times. The enrichment of REE3 and Mn reflects times of more intense weathering, which presumably prevailed during the Atlantic warm and humid climate. In subrecent/recent times, especially the last 100 years, these enrichments may have been at least partially anthropogenically induced

Study of cavernous underground conduits in Nam La (Northwest Vietnam) by an integrative approach, 2005, Tam V. T. , De Smedt F. , Batelaan O. , Hung L. Q. , Dassargues A. ,
This paper presents the result of an investigation of underground conduits, which connect the swallow holes and the resurgence of a blind river in the tropical, highly karstified limestone Nam La catchment in the NW of Vietnam. The Nam La River disappears underground in several swallow holes near the outlet of the catchment. In the rainy season this results in flooding upstream of the sinkholes. A hypothesis is that the Nam La River resurges at a large cavern spring 4.5 km east of the catchment outlet. A multi-thematic study of the possible connections between the swallow holes and the resurgence was carried out to investigate the geological structure, tectonics, cave structure analysis and discharge time series. The existence of the underground conduits was also tested and proven by tracer experiments. On the basis of a lineament analysis the location of the underground conduits were predicted. A remote sensing derived lineament-length density map was used to track routes from the swallow holes to the resurgence, having the shortest length but highest lineament density. This resulted in a plan-view prediction of underground conduits that matches with the cave and fault development. The functioning of the conduits was further explained by analysing flooding records of a nearby doline, which turns out to act as a temporary storage reservoir mitigating flooding of the catchment outlet area

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